Vacuum pump



Sept. 28 1926. 1,601,370

H. C. ODEN VACUUM PUMP Filed NOV. 2. 1923 5 SheetsSheet 1 Sept. 28 1926.1,601,370

' H. c. ODEN VACUUM PUMP Filed Nov. 2. 1923 3 Sheets-Sheet 2 Sept. 281926. 1,601,370

H. c. ODEN VACUUM PUMP Filed Nov. 2. 1923 3 Sheets-Sheet 5 III II II INWINTOR Patented Sept. 28, 1926.

UNITED s'rATEs 1,501,370 PATENT OFFICE.

HENRY CLYDE ODEN, OF SYRACUSE, NEW YORK, ASSIGNOR TO PINE TREE MILKINGMACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 01 ILLINOIS.

VACUUM PUMP.

Application flle'd November 2, 1928. Serial No. 672,810.

This invention relates to certain improvements in vacuum pumps.

The main object of the invention is to increase the efliciency of'astructure of this character, and thereby reduce the cost of operation inthe production of a predetermined amount of vacuum, and a main featureresides in the mechanical operation of the valves in such a manner ands0 timed as to permit the expulsion of all of the air from the cylindersof the structure before the vacuum-producing strokes of the respectivepistons begin, thereby rendering the vacuum strokes of maximumefficiency.

A more specific object is the production of a. pump of this characterthat can be operated at high speed, .and with little expenditure ofenergy when in operation.

Other objects and advantages relate to the details of construction ofthe apparatus and parts thereof, all as will more fully appear from thefollowing description, taken in connection with the accompanyingdrawings, in which Figure 1 is a top plan View of the pump.

Figure 2 is a section on line 22, Figure 1.

Figure 3 is a section on line 3-3, Figure 1.

Figure 4 is a section on line 4-4, Fig ure 1.

Figure 5 is a section on line 5-5, Figure 2. Figure 6 is a section online 66, Figure 4.

Figure 7 is a partial section similar to Figure 2 illustrating thevalves and their operating structure in a somewhat different position.

Figure 8 is a section similar to Figure 2 of a slightly modified form ofstructure.

Figure 9 is a horizontal section thru Figure 8.

The apparatus, as shown, comprises a pedestal 1- carrying a pair ofoppositelyextending axially aligned cylinders and 3, which may be castintegral with the pedestal, and having cylinder heads -1- and 5respectively secured in position in any suitable manner to close theends of the cylinders. These cylinders are spaced apart a distance topermit the inter mediate positioning of the operating apparatus for thepistons 6 and 7 an the valves -8 and -9-. The pistons the opposite wallsof the slot, and preferably these walls are constituted of hardened bars-11 and 12 as shown of substantially sen l-cylindrlcal form, and securedin semicyhndrical recesses in the opposite ends of the vertical slot inthe piston to constitute hardened wearing surfaces for frictionalcontact with the surface of the cam.

The operating shaft 13 extends transversely through the housing of thecylinders 2 and 3 at substantially the central port on of the structure,and is journaled in opposite conical end Walls 14 and .15 connected withthe pedestal 1 and the cylinders 2- and 3- to form a rigid structureopen at its top, and adapted to be substantially closed by a cap orcover -16 extending throughout substantially the length of the cylinders-2 and -3 and spaced vertically from the cylinders, but connected tothem to form a substantially closed structure having an air outlet -17at the upper end of the oil separator 18 which includes baffles 19- and20.

It will be obvious that upon rotation of shaft 13- the cam l0 will movethe pistons -6 and -+7 alternately in opposite directions to producesuccessive vacuum and pressure in the cylinders 2- and 3, and for thepurpose of freely discharging the air from the cylinders -.l and 3 uponthe compression stroke of the respective pistons ports 21- and -22respectively are formed at the ends of the cylinders, and whichcommunicate with the chamber within the hood or cover -16- and for thepurpose of controlling these ports, valves 8- and --9 respectively areprovided, and are connected by an operatingbar 25- which has openings orseats in its opposite ends for the reception of the respective valvestructures -8- and 9- and preferably, as shown, valve structures are ofcup-shaped form and of somewhat rectangular shape, and formed withoutwardly projecting edge flanges, which (1 edge flanges constitute thevalves for 'controlling the ports, as hereinafter described.

boss 28' and secure operating member '25-- as best illustrated in Figure5 so that rocking movement of the yoke 27 will move the valve-operateing-member in 0 posite directions to actuate the valves an properlyposition them for the. operation hereinafter describetn the piston 7starts upon its compression movement, the. valve 9 is just movinginwardly to the point where it opens the port 2 2.- shutting oficommunication between cylinder -3 and port 34- and discharging air fromthe cylinder 3 through hood or cap '--16 and the separator' 18 to theatmosphere. that is entrained with. the air is collected by the baflles19-- and 20 and drops back into the apparatus.

The arrangement of the cams -10- and 26- isrespectively like that shownin Figures 2 and 6. When the cam -10- is" 7 The valve-operating member25 is free in the position shown in Figure 2 where the to slide upon theupper surface of the cylinders -2 and .3--, which surface is formed witha groove for receiving said member so asto guide it in its slidingmovement.

The upper outer surface of the cylinders 2- and -3 are each providedadjacent the ports 21-' and 22-- with laterally extending channels orgrooves that constitute ports which are at all times in communicationwith the respective pipes 31-- and 32 which are connected to the spaceor device to be evacuated, as for instance, to the teat cups of amilking machine through the usual pulsating mechanisms The operation ofthe valves 8 and -9 in connection with the other elements of thestructure constitutes an essential. portion of this invention in thatwhile both the piston and the valve mechanism are actuated from shaft13-, yet they are actuated oi separate cams or other mechanism by meansof which the valves travel somewhat behind the pistons, whereby thepistons are enabled to entirely force the air from the cylinders --2-,and -3 upon their pressure-pro- I ducing strokes so that when they startupon their vacuum-producing stroke they immediately begin to producevacuum. dis tinguished from merely permitting the expansion of a residueof air that has been compressed in the ends of the cylinders.

As shown in Figure 2, the piston -6- has just reached the end of itspressure stroke, and the valve 8 is just arriving at the point where itcompletely closes the port 21 and which would prevent further escape ofair from the cylinder 2. As the piston -6 starts on its vacuum-producingstroke as actuated by cam -10, the valve 8 continues to move toward theouter piston -6- has completed its pressure stroke, the cam 26- issubstantially in the position shown in Figure 6, and where furthermovement of the shaft --13- will continue to shift the valve-carrying oropcrating member 25 in the same direction as the pressure stroke ofpiston 6 so'as to effect-the operation of the valves as heretoforedescribed, and in which the valve 8 continues to move in the directionof 'the pressure stroke of piston 6- even after the piston -6 hasstarted on its vacuum producing stroke in the opposite direction.

This arrangement and operation of the valves permits complete dischargeof the air from the cylinders 2'- and -3 upon the respective strokes ofthe respective pistons, thereby rendering the vacuum producing strokeefiective during the entire stroke for producing vacuum. Further, theuse of mechanically-actuated valves as the valves 8 and 9- permits amuch higher speed operationof the structure than is possiblewith'gravity-actuated valves, and is more positive in its operation andcontrol.

F or the purpose of rendering the operation of the structure of a smoothand balanced character, the pulley 50 has. one side weighted so as tocounter-balance the cam or eccentric 10-, as perhaps best illustrated inFigure 1, and the cam and pulley are so arranged in connection with theshaft 13 that the one balances the other.

In Figures 8 and 9 a somewhat modified form of structure is illustratedin that in place of the hardened inserts or contact members 11 or 12,there is shown a pair of hardened rollers 36 and -37 mounted journaled.in the walls of the respective pistons 6 and 7 and the cam -10 uponshafts 38 and 39 Any oil contacts with these rollers for shifting thepistons endwise as the shaft 13- rotates.

'By this construction friction is consider ably reduced between the camand the parts with which it contacts if that is desired. Otherwise thestructure of Figures 8 and 9 is similar in construction and operation tothat disclosed in the former figures. The

rollers 3G- as here illustrated, are of circular form, but it is obviousthat they may be formed in the nature of eccentrics, if that is desired.

Altho I have shown and described specific constructions as illustrativeof perhaps preferred embodiments of my invention, I do not desire torestrict myself to the details of construction, form or operation of theapparatus and the parts thereof, as various changes may be made in thedetails of form, construction and arrangement without departing fromtheinvention as set forth within the appended claims.

I claim 1. A vacuum pump comprising a base, a pair of cylinders carriedby said base, istons in said cylinders, a port in each cy inder wall,mechanism for simultaneously driving said pistons in oppositedirections, separate valves controllin said ports, a bar engaged witheach of sai valves for simultaneously actuating the valves, and a hoodmounted on said cylinders and constituting a common means ofcommunication between said ports and the atmosphere.

2. A vacuum pump comprising a base, a pair of cylinders carried by saidbase, pistons in said cylinders, a port in each cylinder wall, mechanismfor simultaneously driving said pistons in opposite directions, separatevalves controlling said ports, a bar engaged with each of said valvesfor simultaneously actuating the valves, a cam driven from saidmechanism to actuate said bar, and a hood mounted on said cylinders andconstituting a common means of communication between said ports and theatmos phere.

3. A vacuum pump comprisin a base, a

pair of cylinders carried by sai base, pistons in said cylinders, a portin each cylinder wall, mechanism for simultaneously drivingsaid pistonsin opposite directions, a bar exterior of the cylinders and slidablealong the walls of the cylinders, a pair of cup-shape valves mountedrespectively in the opposite ends of the bar and adapted to control theports in the cylinder walls, and grooves in the cylinder wallsunderneath said cup-shape valves constituting ports permittingcommunication between a pipe line and the space within the cup-shapevalve at the same time that communication exists between the respectivecylinder and the space within the respective cup-shape valve controllingthe port of that cylinder.

4. A vacuum pump comprisin a base, a pair of cylinders carried by saibase, pistons in said cylinders, a port in each cylinder wall, mechanismfor simultaneously driving said pistons in opposite directions, a barexterior of the cylin ers and slidable along the walls of the cylinders,a pair of cup-shape valves mounted respectively in the op osite ends ofthe bar and adapted to control the ports in the c linder walls, groovesin the cylinder walls underneath said cupshape valves constituting portspermitting communication between a pipe line and the space within thecup-shape valve at the same time that communication exists between therespective cylinder and the space within the respective cup-shape valvecontrolling the port of that cylinder, and a hood mounted on thecylinders and constituting means of communication between the ports inthe cylinders and the atmosphere when the respective valves are inpredetermined position.

5. A pump comprisin a base, a pair of cylinders carried by the ase,pistons in the cylinders, a port in each cylinder wall, mechanism forsimultaneously driving said pistons in o posite directions comprlsing arotary sha t, separate valves controlling said ports, a bar engaged withsaid valves for simultaneously actuatin them, a yoke pivoted to the basean engaged with said ar, and a cam mounted on said shaft and contactingwith the yoke to tilt the same about its" pivot to shift said bar andthe valves engaged therewith.

In witness whereof I have hereunto set my hand this 15th day of October,1923.

. HENRY CLYDE ODEN.

